west china medical publishers
Keyword
  • Title
  • Author
  • Keyword
  • Abstract
Advance search
Advance search

Search

find Keyword "Polymer" 33 results
  • CONTRAST STUDY ON DIAGNOSIS OF LYMPH NODES METASTASIS BY CONVENTIONAL PATHOLOGY AND GENETIC DETECTION

    Objective To evaluate the potential of specific mRNA marker keratin 19(K19) to detect micrometastasis by reverse transcriptase polymerase chain reaction (RT-PCR) .Methods One hundred and ninty four regional lymph nodes harvested from 6 cases of benign diseases, 4 cases of breast carcinoma, 5 cases of gastric carcinoma and 12 cases of colorectal carcinoma patients were examined by conventional pathology and amplifying tissue specific K19 mRNA by RT-PCR separately, then the two methods were compared with each other. Results None of the 34 lymph nodes which were pathological metastasis-negative from benign diseases expressed K19 mRNA by RT-PCR, all of the 28 regional lymph nodes which were pathological metastasis-positive from malignant cases showed trains of K19 mRNA by RT-PCR. Of the 132 lymph nodes which were pathological metastasis-negative from malignant cases, 11 lymph nodes were detected with micrometastasis by genetic diagnosis.Conclusion Genetic diagnosis of lymph node micrometastasis is more sensitive than conventional pathology and has diagnostic value and merits further study.

    Release date:2016-08-28 05:30 Export PDF Favorites Scan
  • Expression of T cell receptor Vβ8.3 gene in rats with experimental autoimmune uveoretinitis

    Objective To investigate the expression of T cell receptor (TCR) Vβ8.3 gene on CD4+ T lymphocytes in the rats with experimental autoimmune uveoretinitis (EAU). Methods Eighteen Lewis rats were divided into EAU, complete Freund′s adjuvant, and the control group. Inter photoreceptor retinoid-binding protein (IRBP) R16 peptide was synthesized using Fmoc procedure for induction of EAU. Magnetic absorption cell sorting (MACS) me thod was used to isolate the CD4+T lymphocytes from the spleen of the rats. Flow cytometry was used to monitor the efficiency of isolation. The expression of TCR Vβ8.3 gene segment on CD4+T lymphocytes was determined by fluorescent quantitative polymerase chain reaction. Results EAU was successfully induced in the Lewis rats immunized with IRBP R16 peptide. The proportion of CD4+T lymphocytes isolated by means of MACS was statistically higher than that before isolation (P<0.001). The expression of TCR Vβ8.3 gene segment on CD4+ T lymphocytes in EAU rats was significantly higher than that in the control (P<0.05). Conclusions There is a predominant usage of antigen-specific TCR Vβ 8.3 gene in EAU rats induced by IR BP R16 peptide, which may serve as a target for immunotherapy of EAU. (Chin J Ocul Fundus Dis,2004,20:165-167)

    Release date:2016-09-02 05:58 Export PDF Favorites Scan
  • Artificial Coronary Vascular Stents Fabrication Using Biodegradable Material Compounds of PLA/PGA-co-Chitosan

    Abstract: The first generation scaffolds of bare metal stents (BMS) and the second generation of drug eluting stents (DES) have been widely used in the treatment of coronary heart diseases. However, long term incidences of major adverse cardiovascular events and revascularization treatments are still high because of in-stent re-stenosis and thrombosis. These may be caused by chronic inflammations and vascular wall damages due to persistent metal stents stimulation. What’s more, the eluting drugs within metal stents could also disturb normal growth of vascular endothelial cell, intima, tunica media, smooth muscle and epimysium. Therefore, in order to meet these demands several fully biodegradable scaffolds and drug carried stents have been manufactured using polymers polyester, polycarbonate and polyphosphate, etc. Among them, the security and histo-and hemo-compatibilities of coronary scaffolds made from poly-lactic acid (PLA), poly-glycolic acid(PGA), chitosan as coating, poly-caprolactone (PCL) and other copolymer like poly-lactic-co-glycolic acid (PLGA) have been testified to be sound. Nevertheless, there exist several different shortages for these stents such as tensile strength deficiency and slow degradation. PLA is hard and brittle with slow degradation, while PGA is soft with insufficient support force and fast degradation. Whether stents degrade too fast or too slow, they could not supply sufficient strength and effective support after implantation, and also they may cause target vascular injuries and elastic shrink inducing restenosis and thrombosis in long terms. Using optimized molar ratio component of PLA and PGA with chitosan coating, we can get sound composite materials with better biocompatibility, moderate degradation (approximately 3 - 6 months of completedegradation), adequate mechanical strength, lower inflammatory response and good range of extension, and establish an experiment ground for fully biodegradable vascular scaffolds fabrication.

    Release date:2016-08-30 05:50 Export PDF Favorites Scan
  • Infected endophthalmitis diagnosed by multiplex polymerase chain reaction

    Objective To evaluate the rapid diagnosis of bacterial and (or) fungal endophthalmitis by multiplex polymerase chain reaction (MPCR). Methods MPCR was performed to detect the DNA segment of bacteria and (or) fungi from standard strains and 41 samples of intraocular fluid or vitreous from 38 patients (3 with double eyes and 35 with single), and the results were compared with the cultured bacteria and fungi. Results Five hours after detected by MPCR, bacteria and (or) fungi in 34 out of 41 samples (82.9%) from patients were detected,in cluding bacteria in 26,fungi in 6,and both bacteria and fungi in 2. The positive rate of MPCR was obviously higher than the cultured ones(χ2=9.60, P<0.05). Conclusion With the advantages of rapidity, sensibility, and specificity, MPCR can make for the rapid and definitive diagnosis of bacterial and (or) fungal endophthalmitis. (Chin J Ocul Fundus Dis,2004,20:81-83)

    Release date:2016-09-02 05:58 Export PDF Favorites Scan
  • Molecular biological detection of leber is hereditary optic neuropathy

    Purpose To investigate the relationship between mitochondrial DNA 11778 mutation and clinical characteristics of patients with Laber is hereditary optic neuropathy(LHON). Methods PCR RFLPs (MaeⅢ) and mutation specific primer PCR(MSP-PCR) were used simultaneously to detect mitochondrial DNA 11778 mutation. Results Among 10 subjects who habored 11778 mutation,one was a carrier and nine were patients with LHON.Of the nine patients,six were males and three were females.The age of onset ranged from 12 to 25 years old and the onset interval of the two eyed varied between 0 to 6 months. The visual acuity was CF/10cm-0.1 except one who lost her vision after delivery but recovered gradually.The results of visual field,VEP and color vision were abnormal but ERG and systemic status were all normal. Conclusion Molecular biological detection of the ten subjects showed that they all habored mtDNA 11778 mutation.The existence of carrier and visual recovery imlied that mtDNA mutation was a primary cause of LHON,but other factors such as endocrine disorder might influence the pathogenesis of LHON. (Chin J Ocul Fundus Dis,1998,14:156-158)

    Release date:2016-09-02 06:11 Export PDF Favorites Scan
  • APPLICATION OF COLLAGEN COMPOSITE SCAFFOLD IN VASCULAR TISSUE ENGINEERING

    Objective To review the appl ication of collagen and biodegradable polymer composite scaffolds in vascular tissue engineering, and describe the multi-layering vascular scaffolds of collagen-based material in recent years. Methods The l iterature concerning collagen composite scaffold production for scaffold of vascular tissue engineering was extensively reviewed and summarized. Results As one of the structural proteins in natural blood vessel, collagen is widely used in vascular tissue engineering because of good biocompatibil ity, biodegradabil ity, and cell recognition signal. The vascular scaffolds with biological activity and good mechanical properties can be made by collagen-polymer composite materials. In addition, the structure and function of the natural blood vessel can be better simulated by multi-layering vascularscaffolds. Conclusion Collagen-polymer composite material is the hot spot in the research of vascular scaffolds, and multilayering vascular scaffolds have a brill iant future.

    Release date:2016-08-31 05:44 Export PDF Favorites Scan
  • Mutation and Expression of β-Catenin Gene in Breast Hyperplasia and Breast Cancer

    Objective To investigate the role of β-catenin gene in breast tumorigenesis by detecting mutation and expression of β-catenin gene in breast hyperplasia and breast cancer. Methods Mutation and expression of β-catenin gene in 42 breast cancer, 15 simple hyperplasia and 15 atypical hyperplasia were detected by polymerase chain reaction-single strand conformation polymorphism and immunohistochemistry. Results Normal expression of β-catenin occurred in tissue of breast simple hyperplasia. The rate of abnormal expression of β-catenin in tissue of breast atypical hyperplasia and breast cancer were 26.7% (4/15) and 59.5% (25/42), respectively, which were higher than that of simple hyherplasia tissue (P<0.05). And there was a markedly difference between the atypical hyperplasia tissue and breast cancer tissue (P<0.05). Mutation of β-catenin gene wasn’t detected in this three kinds of tissues. Conclusion Abnormal expression of β-catenin plays an important role in human breast tumorigenesis, reason of abnormal expression of β-catenin isn’t mutation of β-catenin gene. Expression of β-catenin can be regulated by other mechanisms.

    Release date:2016-08-28 04:08 Export PDF Favorites Scan
  • Primary mutation detection of mitochondrial DNA(mtDNA)in Leber′s hereditary optic neuropathy patients

    Optic atrophy,hereditary/diagnosis; Polymerase chain reaction; DNA,mitochondrial; Point mutation; Sequence analysis

    Release date:2016-09-02 06:07 Export PDF Favorites Scan
  • Study on the relativity of human leucocyte antigen B27 subtype gene and acute anterior uveitis

    Objective To probe the association between HLA-B27 subtype and acute anterior uveitis(AAU). Methods The HLA-B27 gene of 49 AAu patients were inspected by means of polymerase chain reaction(PCR), and the B27 subtypes of AAU patients were analyzed by means of DNA sequencing and simulated nucleotide hybridization in computer. Results Twenty-nine(59.39%)of 49 AAU patients were B27 positive, and among them 13 (44.00%)were B2704 and 16(56.00%)B27052 in subtypes.No statistically significant difference in most clinical features were found between the patients with B2704 and B27052.In B27 pasitive patients,8 (seven is B27052 and one is B2704) of them were complicatde with ankylosing spondylitis(AS). Conclusions The AAU patients with either B2704 or B27052 have similar clinical feature.The B27052 gene may be an important factor for complicated AS in AAU patients. (Chin J Ocul Fundus Dis, 1999, 15: 139-142)

    Release date:2016-09-02 06:07 Export PDF Favorites Scan
  • Expression of interleukin18 and signal transducers and activators of transcription 5 in retina of diabetic rats

    ObjectiveTo investigate the expression of interleukin-18(IL-18)and signal transducers and activators of transcription 5(STAT5)in retina of 4-24-week-old diabetic rats, and explore the potential molecular mechanisms involved in diabetic retinopathy (DR).MethodsRetinal gene expression profile of healthy and 8-week-old diabetic rats was established with restriction fragment differential displaypolymerase chained reaction (RFDD-PCR), and the differences was analyzed by bioinformatics. IL-18 and STAT5 were filtrated as the candidate genes of DR. The expression of IL-18 and STAT5 in retina of diabetic rats with the age of 4, 8, and 24 weeks was observed by semi-quantitative reverse transcriptase-polymerase chain reaction(RT-PCR).ResultsThe result of RFDD-PCR showed:expression of IL-18 was higher in healthy retina than that in diabetic one; expression of STAT5 was not found in healthy rats but in diabetic ones. The result of RT-PCR showed:compared with the normal, high expression of IL-18 was found in 4-week diabetic retina, reduced in 8-week one, and decreased to the lowest in 24-week one. The expression of STAT5 was not observed in healthy or 4week diabetic retina, but occurred in 8-week one, and increased in 24-week one. ConclusionThe expression of IL-18 and the activation of STAT5 may relate to the occurrance of DR. The expression of IL-18 doesn′t depend on the activation of STAT5. (Chin J Ocul Fundus Dis, 2005,21:258-260)

    Release date:2016-09-02 05:52 Export PDF Favorites Scan
4 pages Previous 1 2 3 4 Next

Format

Content